14 FOSSIL CIRRIPEDIA. 
CHARACTERES VALVARUM IN SPECIEBUS FOSSILIBUS. 
Carina angusta, introrsim arcuata, ab apice ad marginem basalem paululum dilatata ; 
parvetes valde inflexi, costis manifestis a tecto plerumque disjuncti ; in multis speciebus 
intra-parietibus instruct: intra-parietes nonnunquam superné producti ultra Umbonem, 
qu fit inde subcentralis: parietum linee incrementi peroblique. Scuta plerumque 
subconvera et tenuia, trapezoidea ; marginibus tergalibus lateralibusque angulo insigni 
disjunctis. 
Sect. +. Subcarina adest (solummodo species recentes). 
Sect. tt. Subcarina deest. 
A. Valve quatuordecim: Carine umbone subcentrali. 
B. Valve duodecim: Carine umbone ad apicem posito. 
Valves 12 to 15 in number. Latera of the lower whorl, four or six, with their 
lines of growth generally directed towards each other. Sub-rostrum’ very rarely present. 
Peduncle squamiferous, most rarely naked. 
CHARACTERS OF THE VALVES IN FOSSIL SPECIES. 
Carina narrow, bowed inwards, widening but little from the apex to the basal margin, 
having parietes much inflected, and generally separated by distinct ridges from the 
tectum, and having in many species intra-parictes, which are sometimes produced 
upwards beyond the umbo, so as to make it sub-central; lines of growth on the parietes 
very oblique. Scuta generally only slightly convex and thin, four-sided, the tergal and 
lateral margins distinctly separated by an angle. 
Sect. +. Subcarina present. (This section includes only recent species.) 
Sect. t+. Subcarina absent. 
A. Valves fourteen in number; Carina with the umbo subcentral. 
B. Valves twelve ; Carina with the umbo at the apex. 
The first of the above two paragraphs contains the true Generic description (here leaving 
out the softer parts), as applicable to recent and, as far as known, to fossil species: the 
second paragraph has been drawn up to aid any one in classifying the characteristic valves, 
when found separated, as is most frequently the case with all fossil Pedunculata. ‘The first or 
proper Generic characters would have been more precise, had it not been for the existence of 
one recent species, the 8. vi//osum (Pollicipes villosus, Leach, Calentica Homi, J. H. Gray,) 
which leads into the next genus Pollicipes. I mention this species in order to confess, that 
had the valves been found separately, and their number unknown, they would certainly 
have been included by me under Pollicipes, although, taking the whole organisation into 
consideration, I have determined to include this species under Scalpellum. I need not 
' The meaning of this and all other special terms is given in the Introduction at p. 9. 
